Rozhen Observation Calendar

Which nights are best for a target over the coming weeks. The astronomy mark (darkness × altitude × Moon) is computed for every night; the weather and the overall mark exist only where Open-Meteo has a forecast (the next four days) or ERA5 history (past nights) — the rest is honestly blank.

Best nights for North America Nebula: 03-22 (44), 03-23 (44), 03-21 (41), 03-20 (37), 03-19 (34) — by astronomy; check the weather when the night is within four days.

2047-02-22astronomy score per night — click a bar for that night2047-03-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-02-22 Fri	22	—	unknown	04:55–05:35 (good, 0.67 h)	87.2° 11:10	9.96	3%	59.6°
2047-02-23 Sat	23	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.92	1%	55.9°
2047-02-24 Sun	24	—	unknown	04:45–05:35 (good, 0.83 h)	87.2° 11:00	9.87	0%	54.0°
2047-02-25 Mon	24	—	unknown	04:40–05:30 (good, 0.83 h)	87.2° 10:55	9.83	1%	53.9°
2047-02-26 Tue	25	—	unknown	04:40–05:30 (good, 0.83 h)	87.2° 10:55	9.79	4%	55.7°
2047-02-27 Wed	26	—	unknown	04:35–05:30 (good, 0.92 h)	87.2° 10:50	9.74	9%	59.1°
2047-02-28 Thu	26	—	unknown	04:30–05:25 (good, 0.92 h)	87.2° 10:45	9.7	15%	63.8°
2047-03-01 Fri	27	—	unknown	04:25–05:25 (good, 1.0 h)	87.2° 10:40	9.65	23%	69.4°
2047-03-02 Sat	29	—	unknown	04:20–05:25 (good, 1.08 h)	87.1° 10:35	9.61	31%	75.7°
2047-03-03 Sun	28	—	unknown	04:20–05:20 (good, 1.0 h)	87.2° 10:35	9.56	40%	82.6°
2047-03-04 Mon	30	—	unknown	04:15–05:20 (good, 1.08 h)	87.2° 10:30	9.51	50%	89.7°
2047-03-05 Tue	31	—	unknown	04:10–05:20 (good, 1.17 h)	87.2° 10:25	9.47	60%	97.0°
2047-03-06 Wed	31	—	unknown	04:05–05:15 (good, 1.17 h)	87.2° 10:20	9.42	70%	104.3°
2047-03-07 Thu	32	—	unknown	04:10–05:15 (good, 1.08 h)	87.1° 10:20	9.37	79%	111.3°
2047-03-08 Fri	31	—	unknown	04:10–05:15 (good, 1.08 h)	87.2° 10:15	9.32	87%	117.7°
2047-03-09 Sat	28	—	unknown	04:05–05:10 (good, 1.08 h)	87.2° 10:10	9.28	94%	122.7°
2047-03-10 Sun	28	—	unknown	04:05–05:10 (good, 1.08 h)	87.2° 10:05	9.23	98%	125.7°
2047-03-11 Mon	29	—	unknown	04:00–05:10 (good, 1.17 h)	87.2° 10:00	9.18	100%	126.1°
2047-03-12 Tue	28	—	unknown	03:55–05:05 (good, 1.17 h)	87.2° 10:00	9.13	99%	123.7°
2047-03-13 Wed	29	—	unknown	03:50–05:05 (good, 1.25 h)	87.2° 09:55	9.08	95%	118.9°
2047-03-14 Thu	28	—	unknown	03:50–05:05 (good, 1.25 h)	87.2° 09:50	9.03	88%	112.2°
2047-03-15 Fri	28	—	unknown	03:50–05:00 (good, 1.17 h)	87.2° 09:45	8.98	79%	104.5°
2047-03-16 Sat	28	—	unknown	03:45–05:00 (good, 1.25 h)	87.1° 09:40	8.93	69%	96.2°
2047-03-17 Sun	29	—	unknown	03:40–05:00 (good, 1.33 h)	87.2° 09:40	8.88	58%	88.0°
2047-03-18 Mon	31	—	unknown	03:35–04:55 (good, 1.33 h)	87.2° 09:35	8.83	47%	80.0°
2047-03-19 Tue	34	—	unknown	03:25–04:55 (good, 1.5 h)	87.2° 09:30	8.78	37%	72.6°
2047-03-20 Wed	37	—	unknown	03:10–04:50 (good, 1.67 h)	87.2° 09:25	8.73	27%	66.0°
2047-03-21 Thu	41	—	unknown	03:05–04:50 (good, 1.75 h)	87.1° 09:25	8.67	18%	60.6°
2047-03-22 Fri	44	—	unknown	03:05–04:50 (good, 1.75 h)	87.2° 09:20	8.62	12%	56.6°
2047-03-23 Sat	44	—	unknown	03:00–04:45 (good, 1.75 h)	87.2° 09:15	8.57	6%	54.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-02-22&days=30"
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&days=30&format=csv" -o m31-calendar.csv

One row per night: score_astronomy always, score_weather / score only where a forecast or history exists (null otherwise, with weather_source saying which), best window, dark hours, Moon illumination and separation, transit. 7–60 nights. Errors: 400 with invalid_date or target_unresolved. Results are cached for six hours; calculation version 2026-10-10.1.